Generally, manhole covers and storm sewer grates are supported by a metal casting which is fixed in the road such that the cover or grate is at the same elevation as the road surface. However, when the road is resurfaced or repaired, the casting is considerably below the level of the new road surface such that the cover or grate is also not level with the new surface, creating driving hazards.
In my U.S. Pat. No. 4,582,450 issued Apr. 15, 1986, an adjustment ring is disclosed which can be positioned on the old casting to raise the manhole cover or storm grate to the same elevation as the resurfaced road.
It has been seen that further adjustment capabilities for the adjusting ring are needed. Specifically, castings vary in their size as to the distance between the top peripheral edge and the support shoulder on the inner wall. Accommodation for this need previously would involve selecting from an inventory of different sized rings an adjusting ring which is appropriately sized to fit the casting.
It is thus seen that what is needed is an adjustment ring section which includes common components which when assembled can provide an adjustment ring of any desired height to matingly fit the requirements of a given manhole casting.